The first step to create such a coral pad is done. The concrete blocks lie as they should lie. Now, however, they still have to be connected, otherwise they would spread out during the next storm.
These fixings are made with steel rods and cable ties. How, you see in this video.
By the way, if you are in the area, so on Phuket, are at least rescuediver and want to help to keep the corals a little longer alive, then you can experience some dives with us that you might not experience otherwise.
My video is at DLive